Wednesday, March 4, 2015
Math Note for Authors
This type of construction drives me crazy, but I see it a few times a year.
"A 200 percent reduction."
Wouldn't a 100 percent reduction in anything bring it to zero? I think what the author is usually getting at is "reduced to a quarter of the size."
I checked with a statistician friend who offered the following response:
"The only way you can have a 200% reduction in a quantity is if negative quantities are allowed. In theory, if your company went from a 50K profit a 50K loss, you have had a 200% reduction in profit. But I don't recommend that construction.
"For the record, percentage change is (Current Value - Previous Value) / Previous Value, times 100. Thus, going from 50K to 60K profit is (10/50) * 100 or a 20% increase."
You know what else drives me crazy? That the Google has embedded some crap in its email that turns all text copied and pasted from it into this white background when I put it into my blog -- and that's after putting it into a Word doc, hitting Clear Formatting, saving as Plain Text, and pasting it here.
My email problems, though, pale compared to Mrs. Clinton's, if today's news is any indication. I wouldn't mind at all seeing a (D) alternative or two or three step up. Or seeing Bernie Sanders run the table on the whole lot of them.
Then there's Mark Warner, one of my U.S. senators. Matter of fact, here's a very interesting website: